How We Fight

Colin H. Kahl

From Foreign Affairs, November/December 2006

Summary:  Reports that U.S. troops may have killed 24 civilians in Haditha, Iraq, last November have renewed fears that the U.S. military routinely violates the laws of war. But is the Haditha incident the exception or the rule? In fact, U.S. compliance with noncombatant immunity in Iraq has been relatively high by historical standards, and it has been improving since the beginning of the war.

Colin H. Kahl, Assistant Professor of Political Science at the University of Minnesota, conducted research at the Department of Defense from January 2005 to August 2006 on a fellowship from the Council on Foreign Relations.

The U.S. military has also tried to limit risks to civilians by reviewing its military targets with the collateral damage estimation methodology (CDEM), which uses computer software and human analysis to estimate possible civilian casualties for every target studied. The CDEM requires commanders and their legal advisers to ask themselves five questions to determine whether a given target is a legitimate one. Can they positively identify the person or the site according to the current ROE? Is there a protected civilian facility or significant environmental concern within the range of the weapon to be used? Can damage to that concern be avoided by attacking the target with a different weapon or a different method? If not, how many people are likely to be injured or killed in the attack? Must a higher commander be called for permission? When the targets considered represent a risk of "high collateral damage," the CDEM requires political approval by the secretary of defense and, during major combat, the president.

The ROE governing the use of force by U.S. troops in Iraq have also sought to balance each troop's legitimate right to self-defense with the importance of complying with the laws of war. They attempt to maintain this balance by providing troops with a clear sense of what constitutes a legitimate military target. During major combat in Iraq, the criterion was status-based. Individuals or groups, namely Iraqi military and paramilitary forces, that were "declared hostile forces" under the ROE, could be attacked on sight until they were wounded or they surrendered. As the war transitioned into a counterinsurgency mission and U.S. forces confronted adversaries who were largely indistinguishable from the civilian population, the criterion became conduct-based: U.S. troops must now positively identify a "hostile act" (such as the firing of an automatic weapon in their direction) or a "hostile intent" (such as the brandishing of a rocket-propelled grenade or the planting of an improvised explosive device) before they may fire their weapons.

Based on my interviews and the accounts of troops and embedded correspondents I have reviewed, U.S. forces in Iraq seem generally to have followed the requirement that they positively identify a hostile force, act, or intent before attacking. U.S. commanders have emphasized the need for visual confirmation of a legitimate target before firing. When the naked eye fails, U.S. forces rely on advanced optics. Forward observers are used to identify and "paint" targets, or provide coordinates for laser- or GPS-guided bomb attacks. Air force, navy, and marine fighter aircraft have also been retrofitted with new reconnaissance pods that allow real-time overhead surveillance and streaming video, thereby helping ground forces distinguish insurgents from civilians during raids and combat missions.

Furthermore, U.S. forces have been reluctant to use artillery against insurgents, even when they have been under mortar and rocket fire. Artillery systems (such as howitzers, mortars, and ground-launched rockets) have a large radius of destruction and so have a high potential for collateral damage, especially in densely populated areas. Instead, U.S. forces have either relied on close air support and ground forces that can keep their "eyes on the target" or refrained from attacking altogether. This summer, for example, as I was conducting interviews in the U.S. embassy in Baghdad, the Green Zone was hit by two rockets and two mortars. Although the attack's point of origin -- a residential neighborhood near Sadr City -- was determined quickly, the U.S. military chose not to fire back with artillery.

The U.S. ROE have also emphasized the importance of using proportionate force when engaging legitimate military targets in order to minimize collateral damage. The current rules explicitly require U.S. troops to respond to a hostile act or intent with "graduated" force. Under many circumstances, U.S. forces may engage in deadly violence only after warning their targets and trying nonlethal measures against them to no avail. The U.S. military also frequently engages in "weaponeering" -- selecting the most specifically tailored type and quantity of weapon necessary to produce a desired effect. When air strikes are required, it increasingly relies on precision-guided munitions, such as laser-, GPS-, and optically guided weapons. During the major combat phase of the war in Iraq, 68 percent of the munitions used were precision-guided, compared with 7-8 percent during the 1991 Gulf War, 30 percent in Kosovo, and 60 percent in Afghanistan. The U.S. military has also developed munitions with smaller payloads to ensure that it uses the smallest force necessary, and it relies heavily on penetrating munitions with delayed fuses to confine the damage caused by blasts and fragmentation to the area of impact. Additional mitigation techniques, including adjusting the timing, angles, and azimuths of attacks, have also been regularly employed to reduce risks to civilians.

The number of U.S. air strikes has also declined sharply since the end of major combat, indicating the U.S. military's heightened concern for proportionality. Official figures suggest that U.S. planes launched 18,695 strikes during the first 30 days of the war, compared with just 285 strikes in 2004 and 306 in 2005. Other estimates put the 2005 total at 654. Even with the higher number, however, there were almost as many air strikes per day during the major combat phase (an average of 623) as there were during all of 2005.

THE FOG OF WAR

Despite these steps, the United States' adherence to the norm of noncombatant immunity in Iraq has been incomplete. During major combat operations, the U.S. military went to great lengths to craft targeting procedures and choose weapons that reduced risks to civilians, but the execution was imperfect. When targeting high-value targets under time pressure, U.S. forces acted on intelligence that was insufficient to adequately protect civilians. For example, they relied heavily on intercepts from satellite phones to identify high-value targets of opportunity, according to a Human Rights Watch report, even though the technology used for tracking the coordinates associated with these phones was known to be inaccurate and they lacked the time and the human intelligence to either corroborate their targets' positions or estimate the likely collateral damage. In fact, not one of the 50 time-sensitive attacks U.S. forces waged against high-value targets in this time period killed the intended individual; together, however, they did kill and wound scores of Iraqi civilians. Human Rights Watch also suggests that ground-launched cluster munitions used against Iraqi artillery in residential neighborhoods in Baghdad, Hilla, Naiad, Nasiriya, and elsewhere killed or injured hundreds of civilians during the land invasion and that unexploded ordnance (or "duds") left over from these attacks killed or injured many more in the months following major combat.

After the end of the major fighting, some U.S. ground forces continued to engage in behavior that appears to have violated noncombatant immunity. Suicide attacks by pedestrians and civilian vehicles laden with explosives have continually threatened U.S. forces at checkpoints and temporary roadblocks or driving along supply routes. Sometimes, U.S. troops have fired on unarmed individuals or civilian vehicles that have gotten too close to their positions. Early on, many U.S. checkpoints and roadblocks were poorly marked, and frightened or confused Iraqi drivers often failed to stop their vehicles in time. Convoys of U.S. military vehicles typically display signs warning Iraqi drivers to stay back 50-200 meters or risk being fired on. Unfortunately, unwitting Iraqi drivers have occasionally attempted to overtake the convoys -- with deadly consequences.

Incidents have also occurred during raids and sweeps of Iraqi homes and businesses. Iraqis often complain that U.S. troops are arrogant and abusive during these operations. While searching for weapons and insurgents, U.S. soldiers have sometimes broken down doors, humiliated residents, and destroyed property. Too often, raids have been based on dubious intelligence gleaned from informants seeking to settle scores. And when soldiers and marines have encountered armed resistance from families seeking to defend their homes, they have sometimes responded with disproportionate force.